Leccy MTB and and Leccy bike legislation

So, today as I'm wandering around Canary Wharf there seems to be a TdF Fan Park in Wood Wharf. Lots of doody outlets, information stands, cycle London stuff and a huge bar and screen to watch the Tour on.. Brilliant.
However that's not what this thread is about.

I know we've seen this pic of the Leccy MTB before, but I've seen it in the flesh now.. It'll do 50kph and the Guy who's importing them went up Snowdon on it last week..

Thing is, he said that the legislation around Leccy bikes and restricting them to 15mph has been binned, yesterday it seems the Govt took away that restriction, so no more 15mph law.

How does it work if you do actually have a Full Motorcycle licence ?
Could I ride a De-Restricted Ped-Elec with a proper helmet on the road legally ?
(I`m kind of drawn to an Electric assist cargo bike with the ability to take 2 kids on the back) I do feel that 15mph is quite dangerously slow in modern traffic, 20mph on the roadie is bad enough

It would need to meet the requirements for other mechanically propelled vehicles so would need tax (altho zero rated) lights, indicators etc. It would also need type approval and registration. Good luck finding someone to insure it too!!